1. Technical Field
The present invention relates generally to control devices for cultivators and, more specifically, to a gravity actuated guide for row crops that when mounted on a tractor front axle will enable the operator to compensate for changes in transverse slope by steering the tractor and thereby correctly positioning the cultivating equipment behind the tractor in relation to the rows.
2. Background of Prior Art
Vehicles driven on a sloping terrain will have their rear wheels track lower on the face of the slope than the front wheels. As used herein, the slope refers to the slope of the ground transverse of the direction of travel of the traction vehicle. Normally when using a tractor equipped with cultivating tools, one centers the tractor by aligning the tractor's center with the center of the row of plants being cultivated. Cultivating tools are then properly positioned on either side of the crop row. On sloping terrain, the cultivator, trailing behind the tractor's rear wheels, tracks off center because the tractor's rear wheels are lower on the slope than the front wheels. To properly align the cultivating tools relative to the crop, one must compensate by steering the tractor further up the slope. The degree of such compensation depends on the amount of slope. It requires much experience before one can readily and accurately adjust for changes in slope and even then after a time such work can be fatiguing and marred with error.
Various types of attachments have been proposed for aiding farm machine operators to compensate for variably sloping terrain. Examples of such devices are disclosed in U.S. Pat. Nos. 2,555,954, 2,929,457, 3,104,476 and 1,373,852.
3. Summary of the Invention
The embodiment of the present invention translates the motion of a pendulum member to a second guide arm member by means of a crossbar. The members cooperate in a manner such that the arc of movement of the guide arm is increased relative to the movement of the pendulum movement. The preferred embodiment can be adjusted for particular farm machines and operating conditions. The increased arc of the guide arm and the capability to fine tune the device enables the device to more accurately indicate to the machine operator the degree of compensation required to keep the cultivator tools and crop rows in proper alignment. The guide arm acts as a pointer and indicates where the crop row should be as the farm machine passes over. The operator steers the forwardly moving machine so the crop plants pass under the guide arm calibrated to indicate proper alignment of the cultivator equipment with the crop rows. In its preferred embodiment, the bottom of the guide arm is equipped with a plant gate having a high clearance to aid the operator in following the row of plants, in which case, the operator steers the forwardly moving farm machine in a manner that keeps the plants moving through the gate of the calibrated device mounted on the farm machine to insure proper alignment of the cultivating equipment with the rows of the crop.
Thus, according to the present invention, an extremely simple attachment which can be manufactured at minimum cost, can be readily attached to a conventional farm machine to aid the operator in compensating for changes in sloping terrain. The device can be made adjustable across a wider range to provide accurate readings as to the degree of compensation needed by the operator for a particular tractor and the particular conditions at that time. Other features and advantages of the present invention will be apparent to those skilled in the art from the following detailed description of a preferred embodiment accompanied by the attached drawing wherein identical reference numerals will refer to like parts in the various views.